constraint
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... topology changes) to match address assignment. Or, (b)
avoid constraints on the topology (and topology changes), but require
...
... Internet routing
system is subject to both technological and fundamental constraints.
These constraints restrict the choices of address ...
... subject to both technological and fundamental constraints.
These constraints restrict the choices of address allocation policies
that are practical.
...
... Therefore, the "address lending" policy, if applied appropriately, is
consistent with the constraints on address allocation policies
imposed by hierarchical routing ...